NHTSA probes Grand Cherokee, Ram

The National Highway Traffic Safey Administration said it is investigating potential power steering hose failures that could lead to under-hood fires in about 106,800 2012 Grand Cherokees.

NHTSA also is investing potential rear differential failures that could lead to rear wheel lock-up and loss of vehicle control in about 230,000 2009-2010 Dodge Ram 1500 pickups.

A NHTSA defect investigation is often a prelude to a vehicle safety recall.

NHTSA's Office of Defect Investigation said the power steering hose on the 2012 Grand Cherokee could fail, resulting in power steering fluid leakage in the engine compartment. It said the fluid "may be ignited by hot surfaces in the engine compartment."

In the Dodge Ram investigation, NHTSA said it had received 12 complaints of alleged rear differential failures resulting in rear wheel lock-up, including "one resulting in a crash into a concrete barrier."